#include <iostream>
using namespace std;
class Circle{
    double radius;
    double pi=3.1415926535;
public:
    Circle(double radius){
        this->radius=radius;
    }
    double getArea(){
        return pi*radius*radius;
    }
    double getPerimeter(){
        return 2*pi*radius;
    }  
};

int main(){
    double radius;
    cout<<"请输入圆的半径："<<endl;
    cin>>radius;
    Circle circle=Circle(radius);
    cout<<"该圆的周长："<<circle.getPerimeter()
        <<"，面积："<<circle.getArea()<<endl;
    return 0;
}